1. Field of Invention
The present invention relates to sealing members in general and in particular to a method and apparatus for sealing around a ground piling.
2. Description of Related Art
In many industries, storage tanks are utilized to store or otherwise contain a variety of fluids. Some of such fluids may be hazardous or otherwise polluting to the environment, such as, by way of non-limiting example diesel fuel, glycol, or other chemicals utilized for industrial or commercial applications. Disadvantageously, such storage tanks may periodically have leaks, spills or other failures which may lead to contaminants entering the local soil and polluting the environment.
One common method of reducing possible impact of contaminant spills has been to place the storage tank on pilings inserted into the soil and to then also cover the surrounding soil with a ground sheet. As the ground sheet is required to contain any contaminants escaping from the storage tank, it has commonly been necessary to seal the ground sheet around piling. Previous solutions to the above difficulty have been to seal the ground sheet directly to the piling or to provide a collar extending from the sheet which may then be sealed to the piling.
One disadvantage of such a system is the difficulty of maintaining the seal between the ground sheet and the pilings. In many locations, the ground surrounding such storage tanks may be prone to expansion, contraction, shifting or settling due to the influence of time, water infiltration or ground freezing and thawing. Such fluctuations in ground level may cause the ground sheet to move relative to the pilings making sealing such ground sheet around the pilings difficult. As the connection between the ground sheet and the piling may become stretched due to the movement of the ground sheet past the strength limits of the connection or the ground sheet.